Valve and reverse gearing for steam-engines.



G. J. CLARK. VALVE AND REVERSE GEAEING EOE STEAM ENGINES.

APPLICATION FILED AUG. ll, 1909.

Y Patented Jan, 11,1910.

.m w a M E N 9 MJ m o i m.

DEFIANCE, OHIO, ASSIGNOR OF ONE-HALF TO CHARLES POLLOCK, OF DEFIANCE,OHIO.

GEORGE J. CLARK, OF

VALVE AND REVERSE GEARING FOR STEAM-ENGINES.

To all whom it may concern:

3e it known that I, GEORGE J. CLARK, a citizen of the United States ofAmerica, residing at Defiance, in the county of Defiance and State ofOhio, have invented certain new and useful Improvements in Valve andReverse Gearing for Steam-Engines, of

which the following is a specification.

This invention relates to an improved valve and reverse gearing forsteam engines. This improved valve gearing is particularly adapted foruse upon locomotives though it may be employed upon any form of steamengine.

The object of the invention is the provision of a structure of thecharacter described so arranged that the position of the valves may beshifted without imparting bodily movement to the yoke hereinafterdescribed.

A further object of the invention is the provision of an eccentricmechanism for imparting a rocking movement to the yoke hereinafterdescribed, said eccentric mechanism being so constructed as to operatewith a minimum of friction.

Further objects and advantages of the invention will be set forth in thedetailed description which now follows.

ln the accompanying drawing, Figure 1 is a side elevation of a valve andreverse gear constructed in accordance with the invention, and, Fig. 2is an underside view illustrating the improved valve and reverse gearingapplied to the cylinders of a locomotive.

Like numerals designate corresponding parts in both of the figures ofthe drawing.

eferring to the drawing, the numerals 5 and (3 designate a pair oflocomotive cylinders having the usual valve chests T and 8, the valvesof which are operated by the usual valve stems 9 and 10. The outer' endsof these valve stems are slidably mounted in bearings 11 and 12.Swinging links 13 and 14 are pivotally connected at 15 and 16 to thevalve stems 10. At their opposite ends these swinging links areconnected to bearing blocks 17, said bearing blocks being slidablymounted in rocking yokes 18 and 19. The rocking yokes are rigidly formedwith rearwardly extending eccentric straps 20 and 21, said straps havingelongated openings 22 formed therein and said straps embracing theeccentrics Q3 and 24. These eccentrics are iXedly mounted upon one ofSpecication of Letters Patent.

Application led August 11, 1909.

Patented J an. 11, 1919.

Serial No. 512,362.

the driving axles 25, said aXles carrying the driving wheel indicated at2G. The swinging links 13 are connected by levers 27 with the arms 28 ofbell crank levers, the opposite arms 29 of said bell crank levers beingconnected by a tie rod 30. This tie rod is in turn connected by a rod 31with the usual reverse lever 32 of the locomotive.

lith the parts in the position illustrated in Fig. 1, it is apparentthat the rotation of the driving axle will impart rotation to theeccentrics and they in turn will impart an up and down movement to thestraps 2O and 21. These straps are pivotally mounted in bearings 33through the medium of arms 34, said arms being rigid with the straps 2Oand 21. It will therefore be seen that a rocking movement is imparted totheycke 18 but that there is no back and forth bodily movement of saidyoke as is the case-in the present type of locomotive valve gearing.Through the medium of the links 18, the movement of the yokes 18 and 19is transmitted to the valve stems 9 and 10 to cause them to shift thevalves in the usual manner. Vhen it is desired to reverse thelocomotive, the links are lifted through the medium of the connectionsdescribed between them and the reverse lever. The movement of thereverse lever, it will be understood, causes the bearing blocks 17 totravel to the upper portions of the yokes 18 and 19, and consequentlyreverses the movement of the valves. By providing straps 20 and 21,having the elongated openings therein, for engagement with theeccentrics, the yokes may be mounted for rocking movement as describedwithout having a back and forth movement imparted to them. Furthermore,the eccentrics are engaged by the straps at only two points instead ofentirely around the periphery of said eccentrics. It is thereforeunnecessary to provide a closely machined fit between these members. Theyokes being mounted in bearings upon both sides thereof, hang true andeven, rendering it possible to shift the links 13 with a minimum ofeffort. Vith the present form of locomotive reverse gearing, it isnecessary for the engineer to bodily lift the yokes corresponding to theconnections 18 and 19. Since these yokes are very heavy, the effortrequired to shift them is great.

From the foregoing description, it will be seen that the presentinvention comprises a reverse and valve gearing of comparatively fewparts, one having but very few joints that may become loose, and onethat is very easy to operate. Vhile the elements shown and described arewell adapted to serve the purposes for which they are intended, however,it is to be understood that the invention is not limited to the preciseconstruction set forth, but includes within its purview such changes asmay be made within the scope of the appended claims:

Having described my invention, what I claim is:

l. The combination with an engine and its rotative shaft, of aneccentric carried thereby, a strap having an elongated opening Jiormedtherein in which said eccentric moves, a yoke integral with said strap,bearings upon each side of said yoke, the central portion of said yokebeing pivotally mounted in said bearings and the integral strapextending rearwardly from the central portion of the yoke, a bearingblock slidably disposed within said yoke, a slidable valve stem, and aswinging link, one end of said link l eing pivotally connected to thevalve stem and the other end of said link being pivotally connected tothe bearing block.

2. in a device or' the character described, the combination with aslidably mounted valve stem, of a swinging link, a centrally pivotedyoke, a bearing block slidably I mounted therein with which saidswinging link engages, and means for imparting a rocking movement tosaid pivoted yoke, said means comprising an eccentric and a strapengaged therewith, said. strap being rigidly connected to said yoke, andsaid strap having an elongated opening formed therein for the receptionof the eccentric.

3. ln a device of the character described, the combination with aslidably mounted valve stem, of a swinging link, a centrally pivotedyoke, a bearing block slidably mounted therein with which said swinginglink engages, means for imparting a rocking movement to said pivotedyoke, said means comprising an eccentric and a strap engaged therewith,said strap being rigidly connected to said yoke, and said strap havingan elongated opening formed therein for the reception of the eccentric,and means for shifting the link and its bearing block from one extremityof the yoke to the other.

al. In a device of the character described, the combination of aslidably mounted valve stem, with a. swinging link pivotally connectedthereto, a yoke, bearings mounted upon each side of said yoke in whichsaid yoke is pivotally mounted for rocking movement, a bearing blockslidably mounted in said yoke and with which the swinging link ispivotally engaged, a strap rigidly connected to said yoke and having anelongated opening formed therein, and an eccentric embraced by saidstrap.

In testimony whereof l aiiix in presence of two witnesses.

GEORGE J. CLARK.

my signature TWitnesses z CHARLES PoLLook, HERBERT CURTLAND.

